Through Blender’s Durian project I discovered a great little program called Alchemy. It’s great for producing “inflected chaos” images like the ones below, with lots of cool “randomizer” tools to incapacitate the anal-retentive side of your brain. You can download Alchemy from its creators’ website. The program is free and open, so go for it. Here’s what I got playing around with various settings:
I especially like the “pull shapes” option – you can load up a PDF with vector shapes of your own, and it scatters them loosely along your pen line. The colors can either be fixed or random, as can be the transparency. All in all, one of the coolest “right brain” toys I’ve seen in a while.